Rhizobium leguminosarum

Rhizobium leguminosarum is a bacterium which lives in a mutualistic symbiotic relationship with legumes, and has the ability to fix free nitrogen from the air. R. leguminosarum has been very thoroughly studied—it has been the subject of more than a thousand publications. Rhizobium leguminosarum is a Gram-negative, motile, rod-shaped, aerobic bacterium. R. leguminosarum biovar trifolii, and R. leguminosarum biovar viciae are the most commonly studied biovars of R. leguminosarum, with certain studies seemingly treating R. trifolii as its own species. Research has been carried out into the role that R. leguminosarum could play in promoting growth of canola and lettuce.